Detailed Description

This optimizer is equivalent to an exahaustive search in a discrete grid defined over the parametric space. The grid is centered on the initial position. The subdivisions of the grid along each one of the dimensions of the parametric space is defined by an array of number of steps.

A typical use is to plot the metric space to get an idea of how noisy it is. An example is given below, where it is desired to plot the metric space with respect to translations along x, y and z in a 3D registration application: Here it is assumed that the transform is Euler3DTransform.

If you wish to use different step lengths along each parametric axis, you can use the SetScales() method. This accepts an array, each element represents the number of subdivisions per step length. For instance scales of [0.5 1 4] along with a step length of 2 will cause the optimizer to search the metric space on a grid with x,y,z spacing of [1 2 8].

Physical dimensions of the grid are influenced by both the scales and the number of steps along each dimension, a side of the region is stepLength*(2*numberOfSteps[d]+1)*scaling[d].

Scale type. This array defines scale to be applied to parameters before being evaluated in the cost function. This allows to map to a more convenient space. In particular this is used to normalize parameter spaces in which some parameters have a different dynamic range.

Member Function Documentation

Allow people to add/remove/invoke observers (callbacks) to any ITK object. This is an implementation of the subject/observer design pattern. An observer is added by specifying an event to respond to and an itk::Command to execute. It returns an unsigned long tag which can be used later to remove the event or retrieve the command. The memory for the Command becomes the responsibility of this object, so don't pass the same instance of a command to two different objects

void itk::ExhaustiveOptimizer::AdvanceOneStep

(

void

)

[protected]

Advance to the next grid position.

static void itk::LightObject::BreakOnError

(

)

[static, inherited]

This method is called when itkExceptionMacro executes. It allows the debugger to break on error.

Create an object from an instance, potentially deferring to a factory. This method allows you to create an instance of an object that is exactly the same type as the referring object. This is useful in cases where an object has been cast back to a base class.

Get the command associated with the given tag. NOTE: This returns a pointer to a Command, but it is safe to asign this to a Command::Pointer. Since Command inherits from LightObject, at this point in the code, only a pointer or a reference to the Command can be used.

Methods invoked by Print() to print information about the object including superclasses. Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.